No it is not a sin.
This is hard to understand but god basically tells chrstians that they can do just exactly what they want.
The law was giving to result in life, but no one could keep the law, so death still reigned.
When there is no law there are no rules and regulations. And there you go, Jesus set you free from the law.
Whatever you decide to do, will have consequences, god not prescribing what we should and should not do, but allows us to find that out for ourselves. If you want to be close to god, you will soon realise what type of things drive you away from him. If your heart is turned away from him, no amount of sinning will bother you. But if your heart is full of love for him, you will feel very uncomfortable when you attempt to do some things. Even the thought of doing some things will make you feel uncomfortable. God says, everything is permitted, but not all things are beneficial to you.
How then do you know what is good for you and what is not?. Check your conscience. A god given gift to keep you on the right track. If your conscience is not working properly, then you are straying.
So then, never do anything that you will feel guilty about, because then you have sinned. Sinned against your conscience. Your conscience is your light. If the light inside of you is darkness how dark it is! Your conscience is your light.
If you want to convince yourself that murder, adultery, idolatory, fornication and stuff like that is ok, and you do these things without any sense of remorse, you can be sure your light isnt working. And god said, you will not see his kingdom. Since your conscience isnt a light to you but a snare. And repenting from something you think isnt wrong will never happenen either.
It is for this reason that god writes his law, the law being what is good for us and what is not good for us, on our hearts. Do what you want, but the law written on your heart will cause your conscience to respond correctly to the wrong you want to do.
If you do somehting that goes against your conscience, you suffer wrong. Which is why all things are permitted but not all things are beneficial to you. Suffering for wrong is not nice. But the suffering being beneficial to you to correct your steps.
It helps you clear your consience again, and to remain on the straight and narrow.
The people of the world are not under Gods law. They are a law unto themselves. They are therefore judged by their own words and their own idea of what is right and wrong, and god wont judge you according to what you did wrong from his perspective, but for not doing what you preached to be wrong. Everytime you say it is wrong to lie, if you lie, you will be judged by it. If you are a christian and you lie your consience will burn! It will quickly lead to repentance since you cant stand the burning! And if you repent, you are forgiven. But if you are in the world, then you will lie without feeling remorse, but will just be happy you got away with it. Gods children never get away from doing wrong. They suffer for their wrongs, and that leads to repentance, which means you get back on track.
For the world, there is an upcoming judgement. They will be in the court of god, where all the people you lied to will be present and there evidence will be presented and you will be judged by a court. Israel will for one be judged by the twelve disciples. The hypocrites will be judged by moses. Whoever you subscribe to as a light for your conscience, will be your judge. If you are an atheist and dont believe in god or the devil, then there will be a converted atheist somewhere that will come to the witness stand. If you use the devil as a light for your conscience he will judge you for everytime you did good when he wanted you to do no such thing!. If you use your religion to be a light to your conscience, religious people will judge you. Id rather have god me my judge!
The children of god dont come up for a coming judgement, since they are judged immediately . Their judge standing right at the door. The consequences of those wrongs dont go away in their life, they will suffer for it, so therefore no upcoming court case for them.
Though I walk through the valley of the shadow of death i will fear no evil, for they rod and they staff,(both instruments for correcting and directing your conscience) comfort me.
Sin is anything that is not beneficial to your relationship with god. So since food has little to do with your relationship with him, i dont think it matters. But being a glutton, is not beneficial to you!
Heneni